Corn crops in Illinois and other drought-hit Midwest states have fared better than expected this summer, showcasing the resilience of hybrid varieties, which have come a long way from the drought of 1988, experts said.
"The corn we've got out here right now versus what we had 20 or 25 years ago, it's become almost a completely different animal. It's able to take an awful lot of abuse," said Mark Bernard, a private agronomist.
Major corn-producing regions went weeks without rain during the critical pollination stage this summer, raising fears production would be severely affected.
"When weather conditions are favourable and everything is going your way, you really don't know what's even in there. But when the chips are down, that's when you really get to see the fruits of their labours," Bernard said.
In its September crop report, the US Agriculture Department raised its corn yield projection for Illinois - which was worst hit by the drought - by 11 bushels per acre.
Yield estimates for other drought-stricken Midwest states were also raised by the USDA. Illinois and Iowa typically rank as the country's top two corn producing states.
Agronomists said that along with good subsoil moisture at planting and reasonably mild temperatures at pollination in parts of the Midwest, sturdier hybrids played a major part in the surprising yields.
Over the years, traditional breeders in the United States have mostly focused on improving yields, not on selecting specific favourable plant traits, agronomists said.
But the end-result was often a plant with deep roots that could reach further into subsoils for moisture and could withstand longer periods of severe heat, they said.
"I think that indirectly, by selecting on yield over a diverse range of environments, we're getting this increased stress and drought tolerance," said Kendall Lamkey, director at the Raymond F. Baker Center for Plant Breeding at Iowa State University.